Method and apparatus for memory fault tolerance

Abstract

A plurality of data lines and a plurality of bit lines may be used to write to and/or read from an array of memory cells. A switching element may select among different mappings between the plurality of data lines and the plurality of bit lines. The array may, for example, consist of N memory cells, the plurality of bit lines may consist of N bit lines, and the plurality of data lines may consist of N data lines, where N is an integer greater than 1. For a write operation in which a data block is to be written to the array, a configuration of the switching element may be controlled based, at least in part, on how sensitive the data block is to a faulty memory cell among the array of memory cells.

What is claimed is:  
     
       1. A system comprising:
 one or more circuits comprising a switch, a first data bus that carries data of a first type, a second data bus that carries data of a second type, and a plurality of arrays of memory cells, wherein:
 said data of said first type is more sensitive to errors than said data of said second type; 
 said switch is configured such that:
 when a first one of said plurality of arrays have less faulty cells than a second one of said plurality of arrays, said first data bus is coupled to a first one of said plurality of arrays such that said first one of said plurality of arrays are utilized for storing said data of said first type, and said second data bus is coupled to said second one of said plurality of arrays such that said second one of said plurality of arrays are utilized for storing said data of said second type; 
 when said second one of said plurality of arrays have less faulty cells than said first one of said plurality of arrays, said first data bus is coupled to said second one of said plurality of arrays such that said second one of said plurality of arrays are utilized for storing said data of said first type, and said second data bus is coupled to said first one said plurality of arrays such that said first one of said plurality of arrays are utilized for storing said data of said second type. 
 
 
 
     
     
       2. The system of  claim 1 , comprising a multiplexer, wherein:
 said multiplexer selects among different mappings between a plurality of bit lines of said second one of said plurality of memory arrays and a plurality of data lines that couple said switch to said second one of said plurality of memory arrays. 
 
     
     
       3. The system of  claim 1 , wherein:
 said data of said first type consists of media data; and 
 said data of said second type consists of non-media data. 
 
     
     
       4. The system of  claim 2 , wherein:
 said second one of said plurality of arrays of memory cells consists of N memory cells; 
 said plurality of bit lines consists of N bit lines; 
 said plurality of data lines consists of N data lines; and 
 N is an integer greater than 1. 
 
     
     
       5. The system of  claim 2 , wherein a configuration of said multiplexer is controlled based, at least in part, on which, if any, memory cells of said second one of said plurality of memory cells is faulty. 
     
     
       6. The system of  claim 2 , wherein:
 a first of said mappings maps data lines 1 through N to bit lines 1 through N, respectively; and 
 a second of said mappings maps data lines N through 1 to bit lines 1 through N, respectively. 
 
     
     
       7. The system according to  claim 2 , wherein said one or more circuits reside in a receiver and perform time and/or frequency deinterleaving of received data.